Difficulty: Easy
Merge two sorted linked lists and return it as a new list. The new list should be made by splicing together the nodes of the first two lists.
Example:
Input: 1->2->4, 1->3->4
Output: 1->1->2->3->4->4
Language: Java
/**
* Definition for singly-linked list.
* public class ListNode {
* int val;
* ListNode next;
* ListNode(int x) { val = x; }
* }
*/
class Solution {
public ListNode mergeTwoLists(ListNode l1, ListNode l2) {
if (l1 == null) {
return l2;
}
if (l2 == null) {
return l1;
}
int headVal = 0;
if (l1.val > l2.val) {
headVal = l2.val;
l2 = l2.next;
} else {
headVal = l1.val;
l1 = l1.next;
}
ListNode head = new ListNode(headVal);
ListNode index = head;
while (l1 != null && l2 != null) {
if (l1.val > l2.val) {
index.next = new ListNode(l2.val);
l2 = l2.next;
} else {
index.next = new ListNode(l1.val);
l1 = l1.next;
}
index = index.next;
}
if (l1 != null) {
index.next = l1;
}
if (l2 != null) {
index.next = l2;
}
return head;
}
}